[ENHANCEMENT] Logging eagerly serializes each condition on every feature flag evaluation

[JohanPetersson]

Description

BaseCondition.ToString() serializes on every log-message construction (BaseCondition.cs):

public override string ToString() => JsonConvert.SerializeObject(this, Formatting.None);

It's used inside interpolated strings like $@"Audience condition {this} evaluated to UNKNOWN...", which C# evaluates eagerly before logger.Log(LogLevel.DEBUG, ...) is called. So even with logging disabled, you pay a JsonConvert.SerializeObject per condition on many paths (Evaluate, ExactEvaluator, NumberEvaluator, SubstringEvaluator, ...). This is a real hot-path cost.

Consider gating the log calls behind a level check so the interpolation doesn't run, or cache the serialized condition.

Benefits

Less allocations and resource utilization and feature flags can be used in hot paths.

Detail

No response

Examples

No response

Risks/Downsides

No response

[junaed-optimizely]

@JohanPetersson, Thanks for the report! This looks like a good improvement. I've created an internal ticket to track it for a future optimization. Appreciate you flagging it!